Acid rain is a very serious air and water pollution problem. Many people feel-that it is the most serious pollution problem that we now face. Scientists say that plant and animal life in thousands of lakes in the United States and Canada has already been destroyed by acid rain.
Acid rain forms in the upper atmosphere. There, sulfur dioxide and nitrogen oxides mix with water vapor. They mix with water vapor to form. sulfuric acid and nitric acid. When the vapor condenses and rain falls, the acids fall with it. Every time acid rain falls in a lake, the level of acid in the lake rises. Over time, it can rise to the point at which plants and insects cannot survive. Without plants, which supply oxygen, and insects, which supply food, fish die. The lake becomes a dead lake.
The problem of acid rain has greatly increased in the last few years. Most of the blame for acid rain has been placed on industries. However, some people feel that ineffective air pollution laws are also to blame for the acid rain problem.
A few years ago, many cities and states passed local air pollution laws. The laws were written to impr9ve the air quality in the cities and states. However, the laws usually didn't say anything about the amount of pollution that an industry could pump into the air. Industries found a way to meet the new pollution laws without reducing the amount of pollution they released. They met the new standards by building taller smokestacks.
With the taller smokestacks, air pollutants were released higher up into the atmosphere. The wind carried them far away from the polluting factory. To the people near the factory, the air seemed cleaner. However, the pollution that they once got was now coming down hundreds of miles away in the form. of acid rain.
Which of the following is TRUE about acid rain?
A.It is acknowledged by scientists to be the most serious pollution problem that human beings now face.
B.Many endangered species are on the verge of extinction because of acid rain.
C.Acid rain is composed of sulfur dioxide and nitrogen oxides mixed with water vapor found in the upper atmosphere.
D.Acid rain is mostly found in the United States and Canada.

A.
B.
C.
D.
E.
Which
F.It
G.
B.Many
H.
C.Acid
I.
D.Acid


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2.单项选择题根据下列材料请回答 31~35 题:
Centers of the Great European Cities
The centers of the great cities of Europe are meeting places by tradition-People gather there to drink coffee and chat late into the night.A mixture of locals and tourists make for an exciting,metropolitan atmosphere.
Squares,plazas(广场)and arcades(拱廊)form. the heart of Europe’s cities.
Venice in Italy has the Piazza San Marco—a beautiful square surrounded by shops,churches,restaurants and caf6s.In Barcelona,Spain,LaBosqueria is a lively market with hundreds of stalls selling all kinds of goods.London’s Covent Garden is filled with fruit and vegetable stalls by day and musicians,acrobats(杂技演员)and artists by night.The government buildings at the center of many cities often are architecturally impressive.In London,they serve as a beautiful backdrop(背景)to the coffee tables that line the streets and the banks of the Thames.
These vibrant(有活力的)hearts are the product of centuries of evolution,social historian Joel Garreau told US News and World Report recently.“The reason people think Venice is so great today is you don’t see all the mistakes,”said Garreau-“ Those have all been removed.”Most European cities were laid out before the invention of the car, so bars.restaurants and cafes were near to,people’s homes.Today,the focus of many Europeans’life has moved away from the centers.They live in the suburbs and outskirts,driving to supermarkets to get their supplies.But on a continent where people treasure convention,there are still those who hold onto traditional ways,living and shopping locally.These people.together with tourists,provide the city centers with the reason for existence.
Coffee culture plays a part in keeping these city centers flourishing .this is Particularly true of Paris whose citizens are famous enthusiastic conversationalists this skill is developed over many hours spent chatting over espressos(浓咖啡)and cigarettes.
Religion also plays a role in developing sociable atmosphere.People In Roman Catholic countries used to visit the Church on an almost daily basis.Entire communities would gather in the same building and then move out to the markets.cafes and bars In the surrounding streets.An enormous example of this relationship between church and society is the Duomo。The huge marble cathedral in Florence,Italy IS surrounded by bakeries and coffee shops,and caters not only to the tourist crowds,but also the local community.
第 31 题 It can be inferred from the first paragraph that each big city in Europe
A.has many large squares.
B.has many very magnificent sky-scrapers.
C.draws tourists in large numbers every year
D.has a center where tourists meet their spouses.

A.A
B.
Squares,plazas(广场)and
C.
Venice
D.In
E.London’s
F.The
G.In
H.
These
I.“The
J.”Most
K.restaurants
L.Today,the
M.They
N.But
O.These
P.together
Q.
Coffee
R.this
S.
Religion
T.People
U.Entire
V.cafes
W.An
X.has
Y.
B.has
Z.
C.draws
[.has

3.单项选择题根据下列材料请回答 16~22 题:
Petitions
Petitions(请愿,请愿书)have long been a part of British political life.Anyone who wanted to change something would get a list of signatures from people who agreed to the idea and either send them to the government or deliver them personally to the Prime Minister’s house in London.
They are always accepted at the door by one of the PM'S officials.What happens then? Nothing much,usually.But petitions have always been thought of as a useful way for those who govern to find out what the people really think.
That’s why the UK government Launched its“e—petition”site in November 2006.Instead of physically collecting signatures,all anyone with an idea has to do now is to make a proposal on the government website,and anyone who supports the idea is free to add his or her signature.
The petitions soon started to flow in.The idea was for the British people to express their constructive ideas.Many chose instead to express their sense of humor.
one petitioner called on Tony Blair to stop the Deputy Prime Minister eating SO much”.Another wanted to expel(驱逐)Scotland from the United Kingdom because Scottish football fast never support England in the World Cup.
other petitioners called on the Prime Minister to abolish the monarchy.Some wanted to give it more power.Some wanted to oppose the United States.others wanted to leave the European Union.Some wanted to send more troops to Iraq and others wanted them all brought home.Some wanted to adopt the Euro(欧元).Others wanted to keep the pound.
Yet if some petitions are not serious。others present a direct challenge to government policy.A petition calling on the government to drop plans to charge drivers for using roads has already drawn around 1.8 million signatures.1n response to that,a rival petition has been posted in support of road pricing.And that is also rapidly growing.
There are about 60 million people in Britain.So it is understandable that the government wants to find out what people are thinking.But the problem with the e-petition site seems to be that the British people have about 70 million opinions,and want the Prime Minister to hear all of them.Perhaps he could start a petition asking everyone to lust shut up for a while.
第 16 题 A petition needs to be signed
A.Right
B.Wrong
C.Not mentioned

A.Anyone
B.
They
C.What
D.But
E.
That’s
F.Instead
G.
The
H.The
I.Many
J.
one
K.Another
L.
other
M.Some
N.Some
O.others
P.Some
Q.Some
R.Others
S.
Yet
T.A
U.8
V.1n
W.And
X.
There
Y.So
Z.But
[.Perhaps
.Right
].Wrong
^.Not

6.下列哪些rRNA是在核仁内形成的?( )

A.18SrRNA
B.5SrRNA
C.28SrRNA
D.5.8SrRNA
E.16SrRNA

7.单项选择题根据下列文章,请回答 23~30 题。
Ford
1 Ford’s great strength was the manufacturing process——not invention. Long before he stoned a car company,he was a worker. known for picking up pieces of metal and wire and turning them into machines. He started putting cars together in 1891'.Although it was by no means the first popular automobile,the Model T showed the world just how creative Ford was at combining technology and market.
2 The company’s assembly line alone threw America’s Industrial Revolution into overdrive(高速运转)。Instead of having workers put together the entire car,Ford’s friends,Who were great toolmakers from Scotland. Organized teams that added parts to each Model T as it moved down a line. By the time Ford's Highland Park plant was humming(嗡嗡作响)along in 191 4,the world's first automatic conveyor belt could turn out a car every 93 minutes.
3 The same year Henry Ford shocked the world with the$5.a.day minimum wage scheme,the greatest contribution he had ever made. The average wage in tile auto industry then was$2.34 for a 9-hour shift. Ford not only doubled that. he also took an hour off the workday. In those years it was unthinkable that a man could be paid that much,f0.r doing something that didn't involve an awful lot of training or education. The Wall Street Journal called the plan” an economic crime',and critics everywhere laughed atF0rd.
4 But as the wage increased later to daily$10,it proved a critical component of Ford’s dream to make the automobile accessible(可及的)to all. The critics were too stupid to understand that because Ford had lowered his costs per car,the higher wages didn't matter——except for making it possible for more people to buy cars.
第 23 题 Paragraph l____________

A.Although
B.
2
C.
3
D.a.day
E.34
F.r
G.
4

8.参加维系蛋白质的三级结构的有( )。

A.氢键
B.酯键
C.离子键
D.疏水键
E.共价键

10.单项选择题A.complained
B.argued
C.explained
D.believed

A.complained
B.argued
C.explained
D.believed